Hammer



FIG. 1 is a front view of a hammer showing my new design;

FIG. 2 is a left side view thereof, the right side view thereof appears as a mirror image of the left side view;

FIG. 3 is a back view thereof;

FIG. 4 is an enlarged top view thereof; and,

FIG. 5 is an enlarged bottom view thereof. 

The ornamental design for a hammer, as shown and described. 